What Goldmali says. I wouldn't have dared mate without knowing we had enough homes.
If you are struggling to find *any* homes, really good homes are even harder to come by. Chances are, people who struggle to find homes do end up placing puppies in less than ideal homes, out of desperation.
We've had about 80+ enquiries for our litter and out of those, I accepted only 7 homes. 6 of these were known at birth and on the list, just one puppy didn't have a home at birth. This wasn't for lack of enquiries (80+!) but because I rejected those for being unsuitable.
We don't place pups in homes with kids under the age of 10, there must be an adult available all day, for at least the first 6 months, and we favour working/dog sport/competition/training-orientated homes. Homes which meet all these criteria are really difficult to find, which is why we only had 7 out of 80!!
I'd also say that using a really good stud dog has been more than worth the stud fee many times over - I have had about 2-3 excellent homes via referrals from the stud dog owner, who is very well regarded. This, in itself, is a reason to use a really well qualified and experienced dog rather than your own or one nearby, IMO.
I do know of a breeder who bred his dog (different breed), and could only place 4 out of a large litter of 12. His landlord found out about him having had a litter and said they had to go at 8wks or he'd be evicted. So he took them all to the RSPCA.

All these pedigree and health-tested puppies went, without papers, to a rescue organisation for homing. That really made me think hard and ensure I had a good lot of interest before breeding.